docs: def init_realms(self, realms):
          """
          :type realms: Tuple
          """
          self.realms = tuple(realm for realm in realms
                              if isinstance(realm, realm_abcs.AuthenticatingRealm))
          self.register_cache_clear_listener()
          self.token_realm_resolver = self.init_token_resolution()
          self.init_locking()